When the nine members of industrial-metal band Slipknot throw themselves into their work, the results are broken bones, multiple stitches ... and a debut album that has steadily climbed the charts.

Since Slipknot's appearance on the second stage at last summer's Ozzfest road show, their self-titled album hit #1 on the Billboard Heatseekers chart. Over the past six months, the disc  released last summer  has sold 360,000 copies, according to sales-tracking firm SoundScan.

The band's sound is a churning, rumbling, vein-popping assault on the ears that uses digital hardcore-style technology  a high rate of beats per minute, industrial-strength sampler sounds and low-pitched scratching  layered over standard metal fare.

But that's just the start. Dressed in boiler-room overalls and freakish masks  a fiendish clown, a pig, even a pallid Kabuki mask  Slipknot also pack a hefty visual punch. That visual element is what drew the attention of Roadrunner Records, which released Slipknot, according to the label's Cory Brennan.

But when the nine members hit the stage, the assault begins in earnest. Members routinely engage in the brawling that has given percussionist Shawn Crahan a list of injuries more evocative of a World Wrestling Federation member than a rock star: fractured knuckles, two slipped vertebrae, split collarbones (from doing back flips), a dislocated shoulder, stitches over his left eye, a concussion and numerous scars.

Too Sick For MTV?

As vocalist Corey Taylor said, Slipknot are "hard to explain, but sick to see."

So "sick," apparently, that MTV rejected Slipknot's video for their first single, "Spit It Out" (RealAudio excerpt). Tom Chavez, MTV's director of network standards, would not specify why the network objected to the video but noted that it was "rejected by all stations." The network eventually accepted a video of live footage of the band shot during last year's Ozzfest. Both videos are available on the band's video collection, "Welcome to Our Neighborhood," which has sold 65,000 copies, according to SoundScan.

According to Crahan, the masks evolved from the band's desire to draw the focus away from individual members and let the music do the talking. Crahan said that one day he showed up at a rehearsal wearing his clown mask and the idea took off from there. Each bandmember found a mask that appealed to him and, in Crahan's words, "mutilated it," using leatherwork, zippers and spikes.

The masks, which are strapped on so that they don't fly off during the band's onstage antics, are heavy and hot and, according to interviews in the video, contribute in no small way to the band's aggressive behavior when wearing them. Said turntablist Wilson about his mask, "I don't think very properly when I have it on."

Or even when it's off, according to Taylor. Growing up in Des Moines, Iowa  a town of nothing but "skating rinks and graveyards"  encouraged individuality and imagination, but also "severe psychosis," Taylor said.

The band's aggressive, angry lyrics reflect that psychosis, addressing such topics as death, destruction and suicide. Examples include the refrain from "Surfacing" (RealAudio excerpt): "Fuck it all!/ Fuck this world!/ Fuck everything that you stand for!" Or a line from "Eyeless": "How many times have you wanted to kill everything and everyone?"

But Slipknot's lyrics can also be heartfelt and introspective: "I've felt the hate rise up in me/ Kneel down and clear the stone of leaves/ I wander out where you can't see/ Inside my shell I wait and bleed" (from "Wait and Bleed").

Positive Influence

Crahan, a father of three, is aware of the band's potential influence on young minds. He said it was the band's hope that Slipknot's music be an inspiration to their young fans and a "positive, creative, responsible influence."

Slipknot "doesn't do anything unless it's right, unless it feels right," Crahan said, adding that they take responsibility for everything they say or do. He said the band has recently received criticism for its edgy style.

"It's weird for us, because we've been saying these things from the beginning," he said of the attention the group's chart-climbing album has brought. "But now people are starting to pay attention."